Serine hydroxymethyltransferase 2 (SHMT2) potentiates the aggressive process of oral squamous cell carcinoma by binding to interleukin enhancer-binding factor 2 (ILF2)

Abstract

Oral squamous cell carcinoma (OSCC) is a frequent threatening head and neck malignancy. Serine hydroxymethyltransferase 2 (SHMT2) was identified to be upregulated in OSCC and its high expression was associated with poor patient prognosis. This paper set out to assess the influence of SHMT2 on OSCC progression and the potential mechanisms related to interleukin enhancer-binding factor 2 (ILF2). First of all, reverse transcription-quantitative PCR (RT-qPCR) and western blot examined the expression of SHMT2 and ILF2 in OSCC cells. Cell Counting Kit-8 (CCK-8) and colony formation assays appraised cell proliferation. Terminal-deoxynucleotidyl Transferase Mediated Nick End Labeling (TUNEL) staining was to estimate the apoptotic rate of cells. Further, wound healing and transwell assays verified the migration and invasion of cells. Western blot was adopted to detect the expression of factors related to apoptosis, migration, and epithelial–mesenchymal transition (EMT). The possible interaction of SHMT2 and ILF2 was predicted by a Molecular INTeraction (MINT) and BioGRID databases and determined using co-immunoprecipitation (IP) assay. Subsequently, ILF2 was overexpressed to investigate whether SHMT2 regulated OSCC progression by binding to ILF2. Results implied that SHMT2 possessed increased expression in OSCC cells, and OSCC cell viability, migration, invasion, EMT were inhibited and apoptosis was potentiated after its silencing. ILF2 bound to SHMT2 and ILF2 expression was downregulated after SHMT2 silencing in OSCC cells. Importantly, ILF2 overexpression abolished the suppressive role of SHMT2 interference in the progression of OSCC. Collectively, SHMT2 could promote the progression of OSCC by binding to ILF2.

Structure-Based Design of Transport-Specific Multitargeted One-Carbon Metabolism Inhibitors in Cytosol and Mitochondria

“…This compound was used for the next reaction without further characterization. Methyl 4-((3-Hydroxypropyl)amino)benzoate (25). Methyl 4iodobenzoate (24) (7 g, 26.71mmol) and DMSO (5ml) were added to a mixture of copper iodide (1.02 g, 5.34 mmol) and L-proline (1.23 g, 10.69 mmol), and the resulting blue solution was stirred for 5 min, before adding 3-aminopropanol (10 g, 133.56 mmol).…”

“…To a solution of triphenylphosphine (2.51 g, 9.56 mmol) in dry methylene chloride (100 mL) were added iodine (2.43 g, 9.56 mmol) and imidazole (0.65 g, 9.56 mmol) at 0 °C. The resulting solution was stirred for 10 min, before a solution of methyl 4-((3-hydroxypropyl)amino)benzoate (25) (2 g, 9.56 mmol) in dry methylene chloride (50 mL) was added. The reaction mixture was then quenched with sat.…”

“…Cells were grown until they reached an OD 600 of 0.6, induced with 500 μM IPTG and grown for an additional 16−18 h at 18 °C. The cells were then pelleted and resuspended in 25 Purification of the three enzymes was performed by Ni-NTA chromatography (Gold Biotechnology), as described for His-ATIC. After purification by Ni-NTA, pyridoxal-5′-phosphate (PLP) was added to SHMT1 or SHMT2 in 3-fold molar excess and allowed to incubate for 16−18 h. Final purification of SHMT enzymes was completed with size exclusion chromatography with a Superdex 200 16/60 column (GE Healthcare).…”

“…Importantly, serine catabolism is frequently upregulated in cancer, with SHMT2 and MTHFD2 among the most overexpressed metabolic genes in human cancers compared to normal tissues . Indeed, studies in several cancers suggest that SHMT2 is a bona fide “onco-driver”. − Further, overexpression of SHMT2 is associated with poor prognosis in breast cancer, − lung adenocarcinoma, pancreatic cancer, gliomas, and gastrointestinal cancers . In invasive breast cancer, adrenal carcinoma, and renal cell carcinomas, SHMT2 is likewise overexpressed .…”

Structural Characterization of 5-Substituted Pyrrolo[3,2-d]pyrimidine Antifolate Inhibitors in Complex with Human Serine Hydroxymethyl Transferase 2

“…Serine hydroxymethyltransferase (SHMT) 2 (Uniprot entry Q150818) is a 5′-pyridoxal phosphate (PLP)-associated enzyme that catalyzes the conversion of serine to glycine in mitochondria, resulting in generation of 5,10-methylene tetrahydrofolate (mTHF) from THF (Figure ). SHMT2 is among the most overexpressed metabolic enzymes in a variety of cancers, and SHMT2 expression is widely associated with tumor progression − and patient prognosis (e.g., breast cancer, nonsmall lung cancer, pancreatic cancer). ,,− SHMT2 generates ∼85% of cellular glycine required for synthesis of glutathione, purines, proteins, and porphyrins; the mitochondrial 1C pathway supplies the majority of 1C units (as formate) for cellular biosynthesis in the cytosol. ,− , Further, mitochondrial 1C metabolism from serine is also an important source of NAD­(P)H and generates ATP. , Finally, loss of SHMT2 results in defective mitochondrial respiration due to impaired synthesis of respiratory chain proteins. , …”